dh.texture

Extension: .dh-tex — Type ID: dh.texture

Texture definitions describe compile-time texture operations. The compiler processes them during dh build — runtimes just load the pre-baked results.

Two modes: channel packing (pack) or single source (source). They’re mutually exclusive.

Properties

Property	Type	Required	Description
`$type`	`"dh.texture"`	no	Type identifier
`name`	`string`	no	Display name
`description`	`string`	no	Description
`pack`	`object`	one of	Channel packing map (mutually exclusive with `source`)
`source`	`string`	one of	Single source texture path (mutually exclusive with `pack`)
`size`	`[w, h]`	no	Target dimensions. Omit to keep original size.

The type is inferred from the file extension — $type is not needed in source files. The compiler adds it automatically during builds.

Channel Packing

Combine channels from multiple source textures into a single output. Classic use case: ORM (Occlusion, Roughness, Metallic) packing.

{
  "name": "Body ORM",
  "pack": {
    "r": "textures/occlusion.png@r",
    "g": "textures/roughness.png@r",
    "b": "textures/metallic.png@r"
  }
}

Each key is an output channel (r, g, b, a). Each value is a texture reference with optional @channel suffix.

Defaults for unspecified channels:

RGB channels → 0 (black)
Alpha channel → 255 (fully opaque)

Single Source

Process one texture — resize it or reference a single source:

{
  "name": "Body Diffuse (1K)",
  "source": "textures/body-diffuse.png",
  "size": [1024, 1024]
}

If only one dimension is given in size, the other is calculated to preserve the aspect ratio.

@channel Syntax

The @channel suffix extracts a single channel from a source texture. This works anywhere texture paths are used — in pack values, in source, and in material texture references.

Syntax	Result
`textures/packed.png`	Full RGBA texture
`textures/packed.png@r`	Red channel as grayscale
`textures/packed.png@g`	Green channel as grayscale
`textures/packed.png@b`	Blue channel as grayscale
`textures/packed.png@a`	Alpha channel as grayscale

Works with cross-pallet barcodes too:

io.mltn.base:textures/packed-orm.png@r

The @ separator was chosen because it can’t appear in file paths and doesn’t conflict with : used for pallet references.

Examples

ORM Pack

{
  "name": "Body ORM",
  "pack": {
    "r": "textures/body-ao.png@r",
    "g": "textures/body-roughness.png@r",
    "b": "textures/body-metallic.png@r"
  }
}

Downscale for Performance

{
  "name": "Body Diffuse (Mobile)",
  "source": "textures/body-diffuse-4k.png",
  "size": [512, 512]
}

RGBA with Alpha

{
  "name": "Decal with Transparency",
  "pack": {
    "r": "textures/decal-color.png@r",
    "g": "textures/decal-color.png@g",
    "b": "textures/decal-color.png@b",
    "a": "textures/decal-mask.png@r"
  }
}